Roads Scholar: What's So Rapid About This Ride?

Another bright, shiny new innovation as we struggle towards transportation efficiency: Metro's gradual rollout of the new "RapidRide" bus system. Already zipping around on the east side and the south end, some Seattle neighborhoods will soon have this service (details below), and those neighborhoods will rejoice. Why?

RapidRide does away with a lot of the unknowns of bus-ridership, such as "Did I just miss a bus by 10 seconds?" "Will another bus be along within the next hour?" "Will my bus pull over at every single stop, making my ride an odyssey?"